/***
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2011 INRIA, France Telecom
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.springframework.asm;

/**
 * @author Remi Forax
 */
final class ModuleWriter extends ModuleVisitor {
	/**
	 * The class writer to which this Module attribute must be added.
	 */
	private final ClassWriter cw;

	/**
	 * size in byte of the Module attribute.
	 */
	int size;

	/**
	 * Number of attributes associated with the current module
	 * (Version, ConcealPackages, etc)
	 */
	int attributeCount;

	/**
	 * Size in bytes of the attributes associated with the current module
	 */
	int attributesSize;

	/**
	 * module name index in the constant pool
	 */
	private final int name;

	/**
	 * module access flags
	 */
	private final int access;

	/**
	 * module version index in the constant pool or 0
	 */
	private final int version;

	/**
	 * module main class index in the constant pool or 0
	 */
	private int mainClass;

	/**
	 * number of packages
	 */
	private int packageCount;

	/**
	 * The packages in bytecode form. This byte vector only contains
	 * the items themselves, the number of items is store in packageCount
	 */
	private ByteVector packages;

	/**
	 * number of requires items
	 */
	private int requireCount;

	/**
	 * The requires items in bytecode form. This byte vector only contains
	 * the items themselves, the number of items is store in requireCount
	 */
	private ByteVector requires;

	/**
	 * number of exports items
	 */
	private int exportCount;

	/**
	 * The exports items in bytecode form. This byte vector only contains
	 * the items themselves, the number of items is store in exportCount
	 */
	private ByteVector exports;

	/**
	 * number of opens items
	 */
	private int openCount;

	/**
	 * The opens items in bytecode form. This byte vector only contains
	 * the items themselves, the number of items is store in openCount
	 */
	private ByteVector opens;

	/**
	 * number of uses items
	 */
	private int useCount;

	/**
	 * The uses items in bytecode form. This byte vector only contains
	 * the items themselves, the number of items is store in useCount
	 */
	private ByteVector uses;

	/**
	 * number of provides items
	 */
	private int provideCount;

	/**
	 * The uses provides in bytecode form. This byte vector only contains
	 * the items themselves, the number of items is store in provideCount
	 */
	private ByteVector provides;

	ModuleWriter(final ClassWriter cw, final int name,
				 final int access, final int version) {
		super(Opcodes.ASM6);
		this.cw = cw;
		this.size = 16;  // name + access + version + 5 counts
		this.name = name;
		this.access = access;
		this.version = version;
	}

	@Override
	public void visitMainClass(String mainClass) {
		if (this.mainClass == 0) { // protect against several calls to visitMainClass
			cw.newUTF8("ModuleMainClass");
			attributeCount++;
			attributesSize += 8;
		}
		this.mainClass = cw.newClass(mainClass);
	}

	@Override
	public void visitPackage(String packaze) {
		if (packages == null) {
			// protect against several calls to visitPackage
			cw.newUTF8("ModulePackages");
			packages = new ByteVector();
			attributeCount++;
			attributesSize += 8;
		}
		packages.putShort(cw.newPackage(packaze));
		packageCount++;
		attributesSize += 2;
	}

	@Override
	public void visitRequire(String module, int access, String version) {
		if (requires == null) {
			requires = new ByteVector();
		}
		requires.putShort(cw.newModule(module))
				.putShort(access)
				.putShort(version == null ? 0 : cw.newUTF8(version));
		requireCount++;
		size += 6;
	}

	@Override
	public void visitExport(String packaze, int access, String... modules) {
		if (exports == null) {
			exports = new ByteVector();
		}
		exports.putShort(cw.newPackage(packaze)).putShort(access);
		if (modules == null) {
			exports.putShort(0);
			size += 6;
		} else {
			exports.putShort(modules.length);
			for (String module : modules) {
				exports.putShort(cw.newModule(module));
			}
			size += 6 + 2 * modules.length;
		}
		exportCount++;
	}

	@Override
	public void visitOpen(String packaze, int access, String... modules) {
		if (opens == null) {
			opens = new ByteVector();
		}
		opens.putShort(cw.newPackage(packaze)).putShort(access);
		if (modules == null) {
			opens.putShort(0);
			size += 6;
		} else {
			opens.putShort(modules.length);
			for (String module : modules) {
				opens.putShort(cw.newModule(module));
			}
			size += 6 + 2 * modules.length;
		}
		openCount++;
	}

	@Override
	public void visitUse(String service) {
		if (uses == null) {
			uses = new ByteVector();
		}
		uses.putShort(cw.newClass(service));
		useCount++;
		size += 2;
	}

	@Override
	public void visitProvide(String service, String... providers) {
		if (provides == null) {
			provides = new ByteVector();
		}
		provides.putShort(cw.newClass(service));
		provides.putShort(providers.length);
		for (String provider : providers) {
			provides.putShort(cw.newClass(provider));
		}
		provideCount++;
		size += 4 + 2 * providers.length;
	}

	@Override
	public void visitEnd() {
		// empty
	}

	void putAttributes(ByteVector out) {
		if (mainClass != 0) {
			out.putShort(cw.newUTF8("ModuleMainClass")).putInt(2).putShort(mainClass);
		}
		if (packages != null) {
			out.putShort(cw.newUTF8("ModulePackages"))
					.putInt(2 + 2 * packageCount)
					.putShort(packageCount)
					.putByteArray(packages.data, 0, packages.length);
		}
	}

	void put(ByteVector out) {
		out.putInt(size);
		out.putShort(name).putShort(access).putShort(version);
		out.putShort(requireCount);
		if (requires != null) {
			out.putByteArray(requires.data, 0, requires.length);
		}
		out.putShort(exportCount);
		if (exports != null) {
			out.putByteArray(exports.data, 0, exports.length);
		}
		out.putShort(openCount);
		if (opens != null) {
			out.putByteArray(opens.data, 0, opens.length);
		}
		out.putShort(useCount);
		if (uses != null) {
			out.putByteArray(uses.data, 0, uses.length);
		}
		out.putShort(provideCount);
		if (provides != null) {
			out.putByteArray(provides.data, 0, provides.length);
		}
	}
}
